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https://issues.apache.org/jira/browse/ACCUMULO-4336?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15321469#comment-15321469
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Matt Peterson commented on ACCUMULO-4336:
-----------------------------------------
Hey Josh,
What do you think the patch should do? A defensive approach could minimally
prevent compactions when an empty string is detected, throwing an exception.
That approach doesn't take into account non-empty endRows that would also be
altered, like \"abcd being changed to abcd. The stripping of leading and
trailing quotes within the commons-cli dependency would need to be disabled
(which does not seem to be an existing capability within that API) or Accumulo
would need to do its own parsing/validation. We could potentially replace any
\" characters in the command with \x22 but that may deserve more thought.
Matt
> Command line interpreter escaping issues
> ----------------------------------------
>
> Key: ACCUMULO-4336
> URL: https://issues.apache.org/jira/browse/ACCUMULO-4336
> Project: Accumulo
> Issue Type: Bug
> Components: shell
> Reporter: Matt Peterson
> Priority: Minor
>
> To see the problem, add the following unit test. It will fail.
> {code:title=ShellTest.java|borderStyle=solid}
> Test
> public void scanEscapedQuote() throws Exception {
> exec("createtable test", true);
> exec("insert \\\" f q v", true);
> exec("scan", true, "\" f: q [] v"); // passes
> exec("scan -e \\\"", true, "\" f: q [] v"); // fails
> exec("deletetable test -f", true, "Table: [test] has been deleted");
> }
> {code}
> It appears that the commons-cli library that is used for parsing commands
> will strip the leading \" from the option's value and return an empty string.
>
> {code:title=Parser.java, line 332|borderStyle=solid}
> opt.addValueForProcessing(Util.stripLeadingAndTrailingQuotes(str));
> {code}
> For scans, an empty string as an end row will cause the scan to do nothing,
> which is a reasonable way to fail.
> For compactions, an empty string as an end row will cause the end row to be
> ignored, which can lead to accidentally initiating a compaction over much of
> a table. It is not possible to test the compaction issue with ShellTest
> because MockTableOperationsImpl does not do anything with compactions. But
> the problem code can be seen in the constructor for CompactRange:
> {code:title=CompactRange.java|borderStyle=solid}
> this.endRow = endRow.length == 0 ? null : endRow;
> {code}
> This code will treat an end row of \" as though there was no end row at all.
> The workaround for this is to use the \x22 instead of \".
> Additionally, some characters are not possible to include as either begin or
> end rows. For example, a ! character cannot be escaped but without escaping
> will crash the shell.
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